Cannot recover with NRFgo: "Could not read AHB-AP Id. Could not connect to target."

[Jamie]

See subject. The softdevice is currently installed on the chip (v6.0.0-1.alpha)

I searched online, and found some information that the security state of the chip has been set to "locked". Is this true? How to unlock it?

Thanks! Jamie

[Jamie]

Thanks for the reply--I will give your suggestion a try.

We need to understand what caused this state (the chip no longer was running it's firmware even). In the case of production, we need to know what the potential causes of such a situation, how to prevent it, and how to handle it in firmware if it does happen to a customer's device--any suggestions here?

Thanks! Jamie

[Ole Morten]

Which firmware were you running on the chip when this happened?

The only way I'm aware that can put the chip in such state is to go into system off without any wakeup sources. There should be no reason to put a device into such state in an actual program, so this isn't really something you should need to think about from an end-user's perspective.

If you have a firmware build that is consistently able to put the chip into such state, I'd be very happy to take a look on it.